This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Our overall hypothesis is that early in schizophrenia there are changes in specific brain chemicals. These changes disrupt neuronal function in several distributed brain networks and accounts for the cortical atrophy, cognitive defects and poor psychosocial outcomes of the illness, despite the beneficial symptom reducing effects of antipsychotic medication. Related to the specific study of glutamate and its hypothesized impact on brain imaging and neuropsychological parameters is the hypothesis that imaging and neuropsychological measures can be useful in clarifying psychiatric diagnosis and prognosis. In translating this research project to the clinical arena, the data from brain imaging and neuropsychology will be analyzed to assess the utility of these measures to assist in diagnostic certainty. In addition, some studies have found that brain imaging measures are related to medication response. Therefore, imaging and neuropsychological testing will be correlated with symptomatic outcome at follow-up visits. We propose to study 15 minimally-treated, young patients with a schizophrenia spectrum disorder and 15 matched controls. At baseline, all participants will complete a diagnostic assessment, neuropsychological testing, and MRI scanning. The MRI scans will be repeated at 3, 6, and 12 months intervals.